1. Technical Field
The present invention relates to a method of preparing zinc oxide nanostructures, and more particularly, to a method of preparing zinc oxide nanostructures through hydrothermal growth using a liquid masking layer.
2. Description of the Related Art
Zinc oxide nanostructures are Group II-IV compound semiconductors of a hexagonal crystal structure and exhibit excellent electrical, optical and catalytic properties due to wide band gap and high exciton energy characteristics thereof. Thus, zinc oxide nanostructures have been developed in various ways for application to next generation electronic, optoelectronic, and chemical fields. Particularly, due to luminous characteristics in the UV region, zinc oxide nanostructures have attracted attention in the fields of semiconductor devices, light emitting diodes, chemical sensors, and biosensors, and the like. In the related art, zinc oxide nanostructures are generally prepared through a top-down growth process in which a bulk source material is subjected to wet or dry etching or by a bottom-up growth process in which a vapor or liquid source material is subjected to physical and/or chemical coupling. As the bottom-up growth process, hydrothermal growth allows easy adjustment of various characteristics of zinc oxide nanostructures, such as size, shape, and impurity concentration of the zinc oxide nanostructures, and is advantageously performed at a relatively low process temperature to allow formation of zinc oxide nanostructures on the overall surface of a substrate irrespective of a source material of the zinc oxide nano structures.
However, a patterning technology used in a typical semiconductor process, such as photolithography, micro-contact printing, ink jet printing, and the like is generally performed on a planar substrate and thus has a limit in direct application to non-planar devices.
Therefore, there is a need for development of a technology for patterning zinc oxide nanostructures, which is compatible with various growth methods and synthesis methods and can be applied not only to planar substrates but also to non-planar substrates.